Visitors are one of the most common metrics used in reporting. They display the number of unique people that access your site or fired a specific line item in a variable.

Tracking actual unique visitors to your site is difficult, as there is no fool-proof way to immediately identify actual people. Visitors can use different browsers, clear their browser cookies, access your site from different computers, as well as their mobile device. Each of these scenarios identifies each as a unique visitor (without additional implementation measures implemented).

The Online Marketing Suite has several products and implementation methods, each with its own methods to identify unique visitors. Therefore, you receive slightly different numbers across different products.

How unique visitors are calculated

Using a default JavaScript implementation, a cookie is placed in the visitor's browser, which is used to link hits back to the same visitor. No personal information is stored within this cookie. If cookies are not accepted in the visitor's browser, a combination between user agent and IP address is used instead. Based on this data, Adobe uses several backend variables to assign each hit a visitor ID, unless the s.visitorID variable is seen (this value overrides the automatically assigned visitor ID). The number of unique values within all this data is considered the number of unique visitors.

SiteCatalyst 13.5 and SiteCatalyst 14

Due to the processing capabilities of this platform, almost all instances of Visitors in reports are considered Daily Unique Visitors. There are no instances where visitors are actually reporting unique to the time period. It takes the number of unique visitor IDs for each 24-hour period, and sums them up based on the time period selected. The only exception to this rule is if the metric specifically specifies its granularity, such as Hourly Unique Visitors or Weekly Unique Visitors.

Noncookied visitors are also excluded from many reports, as data collected from these visitors is limited on this platform.

SiteCatalyst 15, Discover, and Data Warehouse

Visitors on this platform are considered unique to the time period selected. SiteCatalyst 15, Data Warehouse, and Discover do not offer the sum of a granular total (that is, the sum of daily unique visitors for a month). The only exception to this rule is in SiteCatalyst 15, under unique visitor reports that specify granularity, such as Weekly Unique Visitors or Monthly Unique Visitors.

Noncookied visitors are also calculated and included in all reports where a visitors metric is available.

Compare unique visitors

Visitors in v14 are higher than visitors in v15/Discover in the same report: SiteCatalyst 14 sums daily unique visitors, while SiteCatalyst 15 deduplicates unique visitors based on the time period. If you have many frequent visitors to your site, this could be the case.

Visitors in v14 are lower than visitors in v15/Discover in the same report: SiteCatalyst 15 and Discover take into account noncookied visitors, which SiteCatalyst 14 does not. If you are using third-party cookies on your site, you could see an increase in unique visitor metrics.